Many cities around the world have ponds and lakes on city property, usually within public enclosures like parks and recreational areas. Often, the water within these ponds and lakes becomes stagnant, while pollutants and waste accumulate and promote algae growth.
Lake Taihu, located in the Yangzte Delta near Shanghai, is the third largest freshwater lake in China with an area of 2,250 square kilometers. In recent years, rapid growth of the industrial and manufacturing sectors in the area surrounding the lake has led to increased pollution in the lake, which provides water to an estimated 30 million residents. A large algae bloom during the height of summer prompted a search for alternative solutions to clean up the water in the lake.
Lake Taihu, China
Credit: Aqua Biofilter Facebook
Australian based Aqua Biofilter was brought in to install what would be the largest aquaponics project in China in an effort to increase the water quality of the lake. The project is over 4 acres in size and features floating beds made out of a variety of locally sourced materials and plants that the surrounding communities could harvest, such as rice. The roots of these plants remain in the water to absorb excess nutrients that was causing the algae blooms. “Three months after project implementation, the water cleared completely with no visible algae and water transparency improved by 250%”, as noted by Aqua Biofilter CEO Tom Duncan.
Comparison of water samples before and after
Credit: Dr. Kangmin Lee
As shown in Lake Taihu, Aquaponics systems remain an effective, low cost solution to water pollution problems that many cities with rapid urban growth are experiencing today. The future of the use of aquaponics systems around the world looks bright, as they come with many environmental advantages while keeping operational costs low.
Hopefully, cities will follow the steps of Lake Taihu in using aquaponics projects to reduce water pollution in public areas and contribute to overall sustainability.